Moss Cellulose 18O Applied to Reconstruct Past Changes in Water Balance of a Boreal Wetland Complex, Northeastern Alberta

2021 ◽  
Author(s):  
John J. Gibson ◽  
Sandra Jean Birks ◽  
Francisco Castrillon-Munoz ◽  
Melissa House ◽  
Dale Vitt ◽  
...  
2020 ◽  
Author(s):  
Kevin J Devito ◽  
Lindsay M James ◽  
Daniel S Alessi ◽  
Kelly Hokanson ◽  
Nick Kettridge ◽  
...  

<p>Peatlands are integral to sustaining landscape eco-hydrological function in water-limited boreal landscapes and serve as important water sources for headwater streams and surrounding forests, and recently for mega-scale watershed construction associated with resource extraction. Despite the regional moisture deficit of the Boreal plains, peatlands and margin swamps exist on topographic highs where low permeability (clogging) layers occur proximal to the surface and are apparently isolated from surface water and local and regional groundwater inputs. The <span>water generating mechanisms (</span>external water sources, internal feedback mechanisms) that<span> enable peatland formation with such </span>delicate water balances<span> in these </span>unique hydrogeologic settings are not well known, and have large implications for understanding the eco-hydrologic role of natural peatlands as well as direct peatland construction in drier boreal landscapes.</p><p>A multi-year sampling campaign was conducted to collect hydrometric, geochemical (DOC, pH, major cations and anions), and isotopic (D/H, <sup>18</sup>O/<sup>16</sup>O) data from a small isolated peatland-margin swamp complex. We explored the relative roles of margin swamps in buffering water loss and generating perched groundwater, shading and wind protection from adjacent forests, snow redistribution in and around the peatland, and wetland feedbacks on maintenance of peatland moisture and ecosystem function. Long-term (18 year) records of water table gradients between the peatland and an adjacent forest combined with 3 year high intensity <!-- Not sure if you mean to separate the long term data from the high intensity data from Lindsey’s project -->water balance calculations show the peatland to be a source of water to adjacent forests during this period and illustrate the dominance of autogenic wetland feedbacks over allogenic controls (external sources) in peatland development at this location. Contrasts in water storage due to the morphometry <!-- Morphometry? -->of the clogging layer appear to the dominant determinants of peatland and swamp form and function. Layers of decomposed peat and fine textured mineral soils in margin swamps with low water storage potential promoted frequent soil saturation and anoxia, limiting forest vegetation growth and water uptake, further enhancing wetland vegetation, water conservation and generation within the wetland complex. Shading and wind protection from adjacent forests appear to influence soil frost duration and atmospheric demand to further reduce evapotranspiration losses contributing to a slight moisture surplus in the wetland complex relative to the adjacent forest. Understanding the water balance and moisture surplus controls in isolated peatlands sheds light on the relative role of allogenic and autogenic controls on peatlands with implications for: 1) assessing regional eco-hydrological roles of peatland and forestland covers, 2) predicting landscape-scale response to environmental change and land use, and 3) directing landscape scale reclamation or large reconstruction projects over a range of geologic settings in water-limited boreal regions.</p>


1998 ◽  
Vol 29 (4-5) ◽  
pp. 303-330 ◽  
Author(s):  
Johnny Mendez ◽  
Larry D. Hinzman ◽  
Douglas L. Kane

Evapotranspiration (ET) from an arctic coastal wetland near Prudhoe Bay, Alaska, was studied during the summers between 1994 and 1996. The purpose of the study was to compare different ET models and to gain a better understanding of evapotranspiration from arctic wetlands. The models used to obtain ET from the watershed were the Bowen ratio energy balance (BREB), Priestley-Taylor (PT), Penman-Monteith (PM), Penman Combination (PC), energy balance (EB), water balance (WB), and WB based on Time Domain Reflectometry (TDR). For one of the ponds, evaporation determined by the EB, PT, PC, BREB, WB, and the aerodynamic (AD) methods were also compared. ET during the summer snow-free period for the watershed averaged 1.45 mm/day obtained via the BREB model. Evaporation from all ponds after spring snowmelt averaged 3.11 mm/day (obtained via the WB). Evaporation rate from ponds was on average twice that of the tundra as a whole. Latent heat flux was the dominant energy sink in wetlands and ponds, whereas sensible heat flux dominated in the drier upland area. The PT and PM models compared well to the BREB (used as the standard of comparison for ET) for 1994 and 1995, once parameters were properly calibrated using 1996 data. The BREB compared well with independent values of ET from the water balance and eddy correlation methods. For the pond, the EB, BREB, WB, PT, and AD methods gave very similar evaporation results for the summer.


2015 ◽  
Vol 65 ◽  
pp. 175-192 ◽  
Author(s):  
P Hlavinka ◽  
KC Kersebaum ◽  
M Dubrovský ◽  
M Fischer ◽  
E Pohanková ◽  
...  

2017 ◽  
Vol 13 (4) ◽  
pp. 186-197
Author(s):  
Tariq Abed Hussain ◽  
◽  
Ghayda Yaseen AlKindi ◽  
Rana Jawad Kadhim
Keyword(s):  
The City ◽  

2020 ◽  
pp. 102-109
Author(s):  
D.KH. DOMULLODZHANOV ◽  
◽  
R. RAHMATILLOEV

The article presents the results of the field studies and observations that carried out on the territory of the hilly, low-mountain and foothill agro landscapes of the Kyzylsu-yuzhnaya (Kyzylsu-Southern) River Basin of Tajikistan. Taking into account the high-altitude location of households and the amount of precipitation in the river basin, the annual volumes of water accumulated with the use of low-cost systems of collection and storage of precipitation have been clarified. The amount of water accumulated in the precipitation collection and storage systems has been established, the volume of water used for communal and domestic needs,the watering of livestock and the amount of water that can be used to irrigate crops in the have been determined. Possible areas of irrigation of household plots depending on the different availability of precipitation have been determined. It has been established that in wet years (with precipitation of about 10%) the amount of water collected using drip irrigation will be sufficient for irrigation of 0.13 hectares, and in dry years (with 90% of precipitation) it will be possible to irrigate only 0.03 ha of the household plot. On the basis of the basin, the total area of irrigation in wet years can be 4497 ha, and in dry years only 1087 ha. Taking into account the forecasts of population growth by 2030 and an increase in the number of households, the total area of irrigation of farmlands in wet years may reach 5703 hectares,and in dry years – 1379 hectares. Growing crops on household plots under irrigation contributes to a significant increase in land productivity and increases the efficiency of water use of the Kyzylsu-yuzhnaya basin.


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